Something both Sony and ASUS agree on is a sleek external design; the VAIO T goes for the all-silver approach while the S400CA throws in a black lid and screen surround. The quality of build materials is more or less the same for both, with metallic exteriors and little or no chassis flex. Where they differ is in physical dimensions; the VAIO T has a 13.3″ screen while the S400CA has a 14″; the S400CA is about a half inch bigger horizontally and vertically and 0.1″ thicker; the weight difference is just under a half pound (3.5 lbs for the VAIO T vs. 3.96 lbs for the S400CA).

Overall there’s no significant difference between them; the S400CA is the better choice if you prefer a bigger screen and vice versa for the VAIO T.

Screen

The S400CA and VAIO T both employ a “TN” type display, the lowest quality panel offered on modern computers. The viewing angles and color reproduction in general are poor. The redeeming factor of these displays is the touch capability, which works well but is kind of awkward to use (reaching out and touching the screen just isn’t a natural gesture in a standard notebook form factor). The VAIO T wins this round because it has an anti-glare display surface; this is a great help in well-lit environments, where glossy displays can have a problem with reflections.

Battery Life

Using our Powermark battery life test, we measured the VAIO T at three hours, 26 minutes and the S400CA at three hours, 51 minutes. The S400CA has a slightly larger battery but also a slightly larger screen to even things out; it wins through and through.

Keyboard and Touchpad

The S400CA’s keyboard suffers from a hollow feel and keyboard flex; it doesn’t provide the most inspiring typing experience. The VAIO T fares better; it feels solid and has better tactile feedback, if just barely. Notebook manufacturers have always had trouble getting the keyboard right on an Ultrabook; the thin design means there’s a limited amount of key travel. It’s all about making the most out of that.

Input and Output Ports

Ultrabooks typically don’t offer much in the way of ports and neither of these notebooks are an exception. The S400CA offers an additional USB port (for a total of three) compared to the VAIO T’s two. Another feature I like about the S400CA is the inclusion of a Kensington lock slot; it’s important to secure your notebook on the go.

Performance

The S400CA and VAIO T offer minimum-strength specifications: 4GB of RAM (the minimum accepted these days), a slow 500GB 5400RPM hard drive and a small SSD cache slaved to the hard drive in an attempt to make it feel faster. The only real difference between these two notebooks is the processor; the VAIO T has an Intel Core i3-3217U dual-core processor while the S400CA has a slightly faster Core i5-3317U dual-core. Either processor is fast enough for everyday usage.

Conclusion

The winner of this roundup is the ASUS S400CA. The differences we noted throughout this comparison are relatively minor but significant at the same time, considering these notebooks are identically priced at $699. The S400CA is slightly larger with a 14-inch screen (the VAIO T is 13.3″) and offers an extra USB port, over 10% better battery life and a faster processor. The VAIO T isn’t a bad choice by any means, though given a choice the S400CA represents a slightly better value.